Another mail_crypt question: figure out to password secure using mysql

[Aki Tuomi]

> On May 26, 2017 at 5:13 PM "dovecot at avv.solutions" <dovecot at avv.solutions> wrote:
> 
> 
> Hello Community,
> 
> (sorry to be more busy, hence more running questions in parallel :) )
> 
> As mentioned in another post, I am testing mail_crypt plugin.
> 
> I was wondering how to really secure the process sothat even the admin 
> cannot have any access to the other users mail content.
> 
> 
> My current config is simple:
> 
> - using per-folder keys (hence the per-user spaces are preserved)
> 
> - put the public/private global keys in base64 format into the sql DB 
> (elliptic algo)
> 
> This obviously allows anyone with read access to the table to decrypt 
> the mails from the filesystem... which I try to prevent.
> 
> 
> Considering of course that all mail users are virtual and do not (and 
> may not) have access to the box itself:
> 
> - how can I secure the keys? I do not see how to handle a assword for them?
> 
> - a solution might be to crypt/decrypt the keys using the user's password?
> 
> - other?
> 
> 
> Thank you for you help.

(sorry for possible duplicate)

You can use userdb attribute mail_crypt_private_password to encrypt the private key. You can use something like

userdb_mail_crypt_private_password = %{pkcs5;salt=<random string>%Lu:password}

to generate the encryption password on the fly from passdb.

Aki Tuomi
Dovecot Oy